Evolutionary implications of tooth replacement in the Paleocene mammal Pararyctes
- 1 January 1983
- journal article
- research article
- Published by Canadian Science Publishing in Canadian Journal of Earth Sciences
- Vol. 20 (1) , 19-22
- https://doi.org/10.1139/e83-002
Abstract
A specimen of the palaeoryctid Pararyctes (Mammalia: Eutheria), from Paleocene strata of Alberta, shows nearly the complete replacement pattern of the dentition. Unexpectedly, premolars at two positions are seen replacing dP4, whereas the premolars at the anteriormost three positions seem not replaced or shed. The resulting total of concurrently functional teeth at five premolar and three molar positions, while mimicking that in certain ancestral eutherians, is clearly a derived character state, achieved independently. Furthermore, this pattern is inconsistent with the assumptions that deciduous and permanent teeth need belong to the same tooth families and that identical adult dental formulae are secure guides to homology.This publication has 3 references indexed in Scilit:
- Mammals from the Upper Cretaceous Oldman Formation, Alberta. III. EutheriaCanadian Journal of Earth Sciences, 1979
- Notes on the dentition and relationships of the Late Cretaceous insectivore Gypsonictops SimpsonCanadian Journal of Earth Sciences, 1977
- Toward a Phylogenetic Classification of the MammaliaPublished by Springer Nature ,1975